E-cigarette cessation interest and quit attempts among young adults reporting exclusive e-cigarette use or dual use with other tobacco products: How can we reach them?

INTRODUCTION There is limited evidence to inform e-cigarette quitting interventions. This mixed-methods study examined: 1) e-cigarette and other tobacco product perceptions and cessation-related factors; and 2) potential behavioral intervention strategies among young adults reporting exclusive e-cigarette use or dual use with other tobacco products. METHODS We analyzed Fall 2020 survey data from 726 participants reporting past 6-month e-cigarette use (mean age=24.15 years, 51.1% female, 38.5% racial/ethnic minority) from 6 US metropolitan areas and Spring 2021 qualitative interview data from a subset (n=40), comparing tobacco-related perceptions and cessation-related factors among those reporting exclusive use versus dual use. RESULTS Among survey participants (35.5% exclusive e-cigarette use, 64.5% dual use), those reporting dual use indicated greater importance of quitting all tobacco or nicotine products (mean=5.28, SD=3.44 vs mean=4.65, SD=3.75, p=0.033), whereas those reporting exclusive use expressed greater confidence in quitting e-cigarettes (mean=7.59, SD=3.06 vs mean=7.08, SD=3.01, p=0.029) and all tobacco and nicotine products (mean=7.00, SD=3.16 vs mean=6.31, SD=3.13, p=0.008), as well as less favorable perceptions (i.e. more harmful to health and addictive, less socially acceptable) of cigarettes, cigars, and smokeless tobacco (p<0.05). Interview participants (50.0% exclusive e-cigarette use; 50.0% dual use) attributed previous failed e-cigarette quit attempts to their inability to cope with social influences, stress, and withdrawal symptoms. Although most expressed disinterest in quitting due to belief of eventually outgrowing e-cigarettes (among those reporting exclusive use) or unreadiness to abstain from nicotine (among those reporting dual use), many acknowledged the need for quitting interventions. CONCLUSIONS Young adult e-cigarette cessation interventions should target risk perceptions, cessation barriers, and social influences/support.


INTRODUCTION
E-cigarette use among young adults (aged 18-24 years) is a significant public health concern 1 associated with other tobacco use and exposure to nicotine and hazardous chemicals 2,3 .In 2021, more than 2 million US young adults reported past 30-day use 2 .The short-and long-term health effects of e-cigarettes require targeted prevention efforts and cessation strategies 3 .
Although many young adults reporting e-cigarette use want to quit 4,5 , cessation services to support quit attempts are limited 6 .Efforts to advance e-cigarette cessation intervention research, have drawn upon previous smoking cessation research 4,6,7 albeit lacking in substantive e-cigarette specific evidence 7 .Moreover, there are few large-scale intervention studies using experimental designs 8 .The existing literature includes only one large-scale, theorybased e-cigarette cessation intervention study for young adults -This is Quitting by Truth Initiative -a text messaging intervention for young people disseminated nationally through social media 4 .To date, >0.5 million young people have enrolled, and data from a large randomized trial among roughly 2600 young adults demonstrated the effectiveness of the program compared to control 9 .
Additional research is warranted to inform e-cigarette cessation efforts, including intervention targets and delivery strategies 6 .It is important to consider the complexities of social influences (i.e.how individuals adjust their behavior to meet the demands of a social environment), outcome expectations (i.e.anticipated, positive or negative, consequences as a result of engaging in a behavior), quit intentions, and dual use with other tobacco products among young adults reporting e-cigarette use 6,[10][11][12][13][14][15][16][17][18][19][20][21] .As such, this mixed-methods study specifically sought to examine: 1) e-cigarette and other tobacco product perceptions and cessationrelated factors that may serve as intervention targets; and 2) potential behavioral intervention strategies among young adults reporting exclusive e-cigarette use or dual use with other tobacco products.

Study overview and design
This mixed-methods study analyzed Fall 2020 survey data and Spring 2021 interview data among young adults reporting e-cigarette use participating in a 2-year, 5-wave longitudinal cohort study, the Vape shop Advertising, Place characteristics and Effects Surveillance (VAPES) study 22 .The parent study, which was launched in Fall 2018, examined the US vape retail environment and its impact on use among young adults from 6 metropolitan statistical areas (MSAs: Atlanta, Boston, Minneapolis, Oklahoma City, San Diego, Seattle) selected based on differences in state tobacco control efforts.

Quantitative data collection
Participants were recruited via ads on social media (Facebook, Reddit) targeting eligible individuals (i.e.aged 18-34 years, residing in one of the MSAs, English-speaking), using relevant headlines and imagery.Individuals who clicked on ads were directed to a webpage with a study description, consent form, and eligibility screener.Purposive, quota-based sampling ensured sufficient representation from those reporting e-cigarette use and individuals who smoke cigarettes (about 1/3 each), sexes, and racial/ethnic minorities.Subgroup enrollment was capped by MSA.
Overall, 65843 users of Facebook/Reddit viewed study ads, 10433 clicked ads, and 9847 consented.Of the 9847, only 2751 were either ineligible or excluded to reach subgroup target enrollment (1472 and 1279, respectively).Among the remaining, 3460 (48.8%) provided complete data and 3006 (86.9%) confirmed participation, after which they were enrolled and were emailed their first incentive ($10 e-gift card) 1 .

Sociodemographics
We included baseline age, gender, race/ethnicity, sexual orientation, education level, and relationship status.

E-cigarette, tobacco, and marijuana use and related factors
At Wave 5, participants reported days of e-cigarette use in the past 6 months; individuals reporting past 6-month use also reported days of use in the past 30.Similar items assessed use of cigarettes, hookah/ waterpipe, little cigars/cigarillos, large cigars, smokeless tobacco, and cannabis.
Past 6-month individuals reporting e-cigarette use indicated the three flavors they most often use, e.g.tobacco, menthol or mint, fruit (Table 1); how often they used nicotine salt (i.e.nicotine base combined with acid(s) allowing nicotine to be inhaled more easily; 0=never, 5=all of the time) [2][3][4][5] ; and device type used most often (disposable, closed cartridge-based [i.e.rechargeable closed system], pod/box mods [i.e.

E-cigarette and other tobacco product perceptions
To measure perceived risk (harm, addiction) and social acceptability, past 6-month individuals reporting e-cigarette use were asked: 'How [harmful to your health/addictive/socially acceptable] do you think the following products are?e-cigarettes, cigarettes, cigar products, hookah, smokeless tobacco, marijuana' (1=not at all to 7=extremely).

Cessation-related factors
To assess importance and confidence in quitting, they were asked: 'How important is it that you quit using e-cigarettes?' and 'How confident are you that you could quit using e-cigarettes if you wanted to?' (0=not at all to 10=absolutely).They were also asked: 'Are you seriously thinking about quitting the use of e-cigarettes?Yes, within the next 30 days; Yes, within the next 6 months; Yes, in more than 6 months; or I am not thinking about quitting the use of e-cigarettes'.Participants were further asked: 'During the past 12 months, how many times did you stop using e-cigarettes for one day or longer because you were trying to quit using e-cigarettes for good?' and 'Compared to a year ago, do you use e-cigarettes less, more, or about the same?'They were also asked to answer questions 1-4 about quitting all tobacco or nicotine products.

Qualitative data
In

Data analysis
Quantitative data were analyzed using descriptive statistics to characterize survey and interview participants.Bivariate analyses were conducted to compare e-cigarette and other tobacco product perceptions and cessation-related factors among past 6-month individuals reporting exclusive e-cigarette use versus dual use with other tobacco products.Analyses were conducted in SPSS 28.0, and alpha was set at 0.05.
Qualitative data were analyzed in NVivo 12 (QSR International) using thematic analysis methodology.Transcripts were systematically coded for patterns and recurring themes (as well as unusual or noteworthy themes) by a minimum of 2 coders and cross-checked for agreement regarding the application of the codes.Team discussions took place regularly in which the codebook themes were re-defined, inclusion and exclusion criteria set, and representative passages identified.Discrepancies regarding code choices were resolved through discussion in a process of constant comparison until consensus was reached (Kappa=93.3%).Interrater reliability was calculated for each code via intra-class correlation coefficients and deemed acceptable if ≥0.80.Content codes were used to thematically group similar interview text; themes were then organized into overarching domains based on use-profile (i.e.those reporting exclusive use of e-cigarettes versus dual use with other tobacco products) and compiled with representative quotations (edited for readability).Balancing the controversy in qualitative research regarding whether to quantify qualitative results, we chose to further indicate the frequency with which participants reported themes by 'quantifying' them as: 'most' (≥75%), 'a majority' (>50%, <75%), 'many' (nearly 50%), 'some' (≥20%), 'several' (<20%), and 'a few' (<10% of participants) 24,25 .

Quantitative results
In this sample of individuals reporting past 6-month e-cigarette use (n=726), average age was 24.15 years (SD=4.84),51.1% were female, 35.5% sexual minority, 73.6% White, 4.4% Black, 10.2% Asian, and 12.1% Hispanic (Table 1).Among the 726 individuals reporting past 6-month use of e-cigarettes, 35.5% reported exclusive use of e-cigarettes and 64.5% reported dual use with other tobacco products.In terms of e-cigarette use characteristics, 84.8% used in the past 30 days, and the most used flavors were fruit (69.1%), menthol/mint (49.0%), and candy (27.0%).Additionally, 21.5% most often used disposable devices, 25.9% closed cartridge-based devices, and 47.8% pod/box mods; 43.7% used nicotine salt at least some of the time.
As shown in Table 2, perceived harm to health and perceived addictiveness related to cigarettes, cigars, and smokeless tobacco products were greater among those reporting exclusive e-cigarette use versus dual use (all p<0.05); marijuana, however, was viewed as being more addictive among those reporting dual use (p=0.006).Those reporting exclusive use (vs dual use) also perceived cigarettes, cigars, and smokeless tobacco products as being less socially acceptable (all p<0.001).
Regarding cessation-related factors, participants reporting dual use indicated greater importance of quitting all tobacco or nicotine products (mean=5.28,SD=3.44 vs mean=4.65,SD=3.75, p=0.033).However, those reporting exclusive e-cigarette use expressed greater confidence in
The average number of days of e-cigarette use was 27.63 (SD=4.97).Among interview participants, 50% reported past 30-day use with other tobacco products (most commonly cigarettes) and 55.0% reported past 30-day use of marijuana.See Table 3 for themes, subthemes, and selected quotes related to qualitative findings below.

E-cigarette and other tobacco product perceptions and cessation-related factors
Almost all participants (regardless of dual use status) generally endorsed low perceived risks towards e-cigarette use; cigarettes were perceived as most harmful to health and more addictive than any amount of e-cigarette use.On the other hand, marijuana was generally regarded as less harmful than e-cigarettes: 'Vaping nicotine [is more harmful and addictive than marijuana] just because I've heard of a lot more health concerns about that online.' (Minneapolis, current use of marijuana) and least likely to cause addiction across the various tobacco products.
Most individuals reporting exclusive use of e-cigarettes indicated that e-cigarettes were less detrimental than cigarettes due to the absence of combustion: 'The combustible [aspect] of proper cigarettes seems worse to me.… Just breathing something on fire versus something that's just warmed up seems worse.' (Seattle, ever use of cigarettes and marijuana) and other harmful chemicals: 'I would say smoking cigarettes [is more harmful] because of the chemicals and heavy metals that are in there.' (Atlanta, ever use of cigarettes and current use of marijuana) However, those reporting dual use often described their risk perceptions of e-cigarettes within the context of other tobacco product use.For example, although some individuals reporting dual use were able to recognize that e-cigarettes can be as addictive as cigarettes, they perceived e-cigarettes as less harmful than cigarettes and other tobacco products: 'The nicotine itself [   Table 3. Continued impact of use on their lungs and lung functioning:

'[Vaping causes] shortness of breath and chest pain. … I've been to the doctor a few times because of chest pain; I thought I was having a heart attack or had cancer.' (Oklahoma City, current use of cigarettes, other tobacco products, and marijuana)
'There were some kids in my high school that got popcorn lung … which is not healthy.'(Seattle, current use of cigarettes and marijuana) When discussing their general interest in, prior attempts at, and barriers to e-cigarette cessation, participants reported a range of responses.While feelings of disinterest in immediate e-cigarette cessation were clearly expressed among most of the participants, the reasons behind the low interest differed across the user groups.Individuals reporting exclusive use of e-cigarettes felt confident that e-cigarettes were just going to be something that they would eventually: 'grow out of, [particularly] as less and less of [their] friends seem to be doing it.'(Seattle, no past/current tobacco product or marijuana use) They frequently expressed the lack of urgency to quit because use served as a temporary distraction: 'It goes back to the whole thing of me being bored -my reason for vaping.For me, it's more about distracting myself [from the boredom].'(San Diego, ever use of cigarettes and marijuana) Potential negative social impact and changes were additional factors impacting interest e-cigarette cessation among individuals reporting exclusive use: 'When everyone is sitting around smoking or vaping, it's kind of difficult to not take part in it.'(Boston, ever use of cigarettes and current use of marijuana) On the other hand, those reporting dual use commonly indicated that, while they would like to eventually cut out all forms of nicotine use, it was not something that they were quite ready for: 'Eventually, yes.But at the moment, not really.... [Vaping] is not something I want to [do] forever because it is an addiction.Sometimes it feels like I don't really have the choice in it.But at the moment, I'm kind of okay with that.' (Oklahoma City, current use of cigarettes, other tobacco products, and marijuana) However, some individuals reporting dual use shared that their awareness of the long-term health risks from e-cigarettes, such as lung injury, prompted quit attempts: '

I have heard of ["popcorn lungs"] and that was around the time whe[n] I started cutting down a lot [on vaping].' (Seattle, current use of cigarettes and marijuana)
Individuals reporting exclusive use of e-cigarettes versus dual use with other tobacco products shared similar experiences regarding prior quit attempts or barriers to quitting.Both acknowledged that previous unsuccessful quit attempts were either due to their inability to deal with the day-to-day stressors: 'I've gone around two or three times, for two weeks without it.But  While nearly all participants, regardless of dual use status, described e-cigarettes difficult to quit: 'I feel like it would be a lot more difficult to quit using e-cigs because I think I am probably a lot more addicted to them than cigarettes'.(Minneapolis, ever use of cigarettes and current use of marijuana) many also identified cost as a motivator for quitting: 'I just don't want to spend as much on nicotine [to vape] anymore.' (Seattle, ever use of cigarettes and current use of marijuana)

Potential behavioral intervention strategies
In terms of message-related content and considerations, Another consideration for an effective e-cigarette cessation program for young adults, mentioned across both prompted and unprompted settings by many individuals reporting exclusive use of e-cigarettes and a majority of those reporting dual use, is the inclusion of peer coaches providing them 'real time' support via text messages 'when needed' (Minneapolis, ever use of cigarettes, other tobacco products, and marijuana); this would provide a more 'convenient' means for young adults to engage in cessation activities, as well as some 'privacy' during social situations when cessation support may be most needed (Boston, current use of cigarettes and marijuana).Most individuals reporting dual use also emphasized that the coach should be: 'an actual person that you're talking to so that it would be more relatable and [not] feel so robotic.' (Oklahoma City, current use of cigarettes, other tobacco products, and marijuana)

DISCUSSION
This mixed-methods study revealed that young adults who reported using e-cigarettes generally held lower perceptions of risk associated with e-cigarette use in comparison to other tobacco products, particularly traditional cigarettes.Notably, irrespective of their dual use status, young adults who reported e-cigarettes use perceived e-cigarettes as posing the least harm to health among all tobacco and nicotine products, except for marijuana.Our qualitative findings yielded substantiating evidence and illuminated these quantitative results.The reduced risk perceptions can be attributed to several factors, including a lack of self-awareness regarding their own e-cigarette usage patterns and habits, especially when contrasted with the smoking intensity and inhalation associated with other tobacco product use.Additionally, beliefs related to e-cigarette addiction and a general lack of knowledge regarding the potential health consequences of e-cigarette use played a prominent role.
Many of our participants also expressed a lack of immediate interest in quitting e-cigarettes.Interestingly, those reporting dual use indicated greater importance of quitting all tobacco or nicotine products, yet they also exhibited lower confidence in achieving this goal compared to participants exclusively using e-cigarettes.Our interview data Tob.Prev.Cessation 2023;9(November):33 https://doi.org/10.18332/tpc/172416provided further insights into these perceptions: individuals reporting exclusive use of e-cigarettes were confident in eventually outgrowing this habit, while those reporting dual use recognized their current unpreparedness to abstain from all nicotine products.
Recognizing that risk perceptions are proximal predictors of e-cigarette use and cessation behavior, our study findings emphasize the critical necessity for researchers to purposefully address the lowrisk perceptions of e-cigarettes among young adults, often linked to their limited knowledge of the potential health ramifications of e-cigarettes.For instance, participants frequently highlighted the importance of including information about the science and health effects of e-cigarettes 26 , strategies for managing withdrawal symptoms, and guidance on finding healthy and effective alternatives to e-cigarettes in intervention and message-related content.
Consistent with existing literature 6,27 , participants in both user groups emphasized the need for an effective behavioral intervention that not only provides strategies for overcoming the complex obstacles to cessation but also tailors messaging to accommodate their unique user profiles 6,27 .E-cigarette use among young adults is driven by diverse factors [28][29][30] , including peer influence [28][29][30] and stress 28 .Those reporting exclusive use of e-cigarettes stressed the importance of addressing the social norms related to e-cigarettes, while those reporting dual use emphasized the need for specific coping strategies for daily stressors 21 .To enhance the relevance of messaging among individuals reporting exclusive use of e-cigarettes, intervention efforts should focus on reducing social cues associated with e-cigarette use and challenging the perceived social acceptability of e-cigarettes.For those reporting dual use, messages should explicitly target the challenges of coping with stress without resorting to e-cigarettes 21 and should offer guidance on managing negative mood and withdrawal symptoms through techniques like relaxation training and physical activity.Key considerations to address cessation among individuals reporting dual use may also include highlighting the evidence regarding the health effects of dual use versus exclusively using e-cigarettes to discourage either new or continued cigarette smoking.
Finally, participants in both user groups expressed a desire for an 'interactive' program, potentially involving peer coaches (young adults who recently quit or are attempting to quit) providing ongoing cessation support either in-person or online.These findings align with the smoking cessation literature, which emphasizes the effectiveness of live coach/ counselor-enhanced mobile health programs among young adults 31,32 .This further underscores the utility of such programs in reaching and engaging this population in vaping cessation.Given the complexity of e-cigarette use and its potential interactions with marijuana and other nicotine/tobacco products 3,21 , personalized counseling should also be considered to address the multifaceted challenges of cessation 12,[33][34][35] .

Limitations
Current findings are limited in their generalizability to other young adults due to our sampling strategy (e.g.recruiting roughly a third of individuals reporting past 30-day use of e-cigarettes and cigarettes) and attrition across waves of data collection.Participation in a longitudinal cohort study and across prior waves of data collection may have resulted in a unique sample.Additionally, data analyzed here are cross-sectional and only among individuals reporting current use of e-cigarettes, thus not capturing longitudinal associations or those reporting non-use, including those who may have quit using e-cigarettes by Wave 5 (Fall 2020), who differ relative to those reporting use 6 .

CONCLUSIONS
Current findings emphasize the crucial demand for enhancing e-cigarette cessation interventions and messaging to accommodate the diverse needs, preferences, and usage patterns observed among different subgroups of individuals who report e-cigarette use.First and foremost, it is imperative to design targeted interventions that can adapt to the evolving needs of the varied profiles of young adults who report e-cigarette use, addressing their physical, mental, and emotional requirements.Additionally, these interventions should provide longterm support for individuals who require extended assistance.Secondly, recognizing the multifaceted needs of distinct groups of young adults reporting e-cigarette use, it becomes essential to offer multiple modes of delivery and engage peer coaches as interventionists who can provide real-time support.This approach holds the potential to increase quit rates significantly 36 .Lastly, ongoing surveillance of young adults' responses to e-cigarette cessation intentions and barriers is necessary, particularly while considering their usage profiles, such as dual use.This is vital due to the limited existing research and the potential unintended consequences (e.g.individuals switching to potentially more harmful cigarettes) that could occur in the absence of clear messaging and accurate interpretation of intervention messages aimed at promoting e-cigarette cessation among young adults, especially those reporting dual use.

Table 1 .
Sociodemographic characteristics and e-cigarette and other substance use behaviors among young adults in a cohort study who reported past 6-month e-cigarette use and participated in survey assessments in Fall 2020 (N=726) and/or who reported past 30-day e-cigarette use and participated in semi-structured interviews in Spring 2021 (N=40) Continuedrechargeable open system], other).

Table 3 .
Risk perceptions; cessation interest, history and barriers; and reactions to vaping cessation intervention strategies among young adults who participated in Spring 2021 semi-structured interviews and reported past 30-day exclusive e-cigarette use or co-use with other tobacco products (N=40)

cigarette and other tobacco product perception and cessation-related factors Risk perceptions Smoking cigarettes more harmful than vaping due to
I believe that smoking is way, way worse.And it's because you're literally lighting something on fire and inhaling direct carcinogens versus if you have a vape, that's well maintained, the product is never getting to the point of being smoke, it's vapor.So, it's a different combination of things.I wouldn't say it's 100% safe, because you're obviously putting something in your lungs that shouldn't be there.But it is safer than putting smoke into your lungs.(San Diego, ever use of cigarettes and marijuana)

and barriers to vaping cessation No interest in vaping cessation now, but possibly in the future
*As of right now, it's like, I mean, unless I do get some debilitating health effect.That'll require me to stop.I don't really see any reason to stop.(Seattle, ever use of cigarettes and marijuana)

No interest in vaping cessation*
Oh, to be brutally honest.No, not really.It gets me through a day.It allows me a way to calm myself down at the end of the day.It's better than going out and doing drugs and drinking and being a bum.(Minneapolis, no past/current use with other tobacco products or marijuana) cigarettes, cigars, etc.So I know that much from time to time eliminate it altogether, for my health.(Boston, ever use of cigarettes and marijuana) Finances as a vaping cessation motivator* Definitely financial, because I can't do both.There's been times when I can, but right now with a job and all of that, I can do one or the other income wise.(Seattle, current use of cigarettes and marijuana)

Potential behavioral intervention strategies Message-related content and considerations Information on science and health effects
else kind of like it's I do that a lot.Where I'll just like have my juul like just kind of hanging out in my mouth without actually hitting it.(OKC, current use of cigarettes and marijuana)

Interaction/support from coaches and/or peer counselors*
+ Inclusive of individuals reporting current use of marijuana.*Similarities among individuals reporting exclusive user of e-cigarettes versus co-users with other tobacco products.